Official Ampeg Portaflex Club

Welcome to the greatest and most exclusive bass club on Talkbass since the Rock Stars Who Use Behringer Amps Club! This is a place to post pics, swap tonal secrets, and discuss the different tones of the greatest low-power bass amps known to man...the Ampeg Portaflexes.

The only qualifications for joining is you must own an Ampeg Fliptop and have a pic you can post so we can ooh and aah over it. Optionally, please tell us a little of the history of your amp(s), any mods you've made, anything special about the speaker, etc. I will make one exception to the Fliptop rule...if anyone owns an Oliver Powerflex bass amp with the motor that raises and lowers the head, you are also permitted to join the club and you are highly encouraged to post a lot of pics.

Here is a pic of my two Fliptops...the first is a 1964 B-15NC that I recently had completely restored by Jess Oliver, the amp's inventor. This thing was a mess when I got it. The previous owner bought it from a guy for $50 because he had dropped it and made a total mess of the power transformer and dented up the chassis pretty badly, and it was rusty and very neglected. The cab was also covered badly in generic black tolex and had some crappy 90's Eminence PA speaker. I bought it for $150 and used the heck out of it for 7 years, and decided to get it restored earlier this year. Jess recovered the cab and dolly and added new hardware, put new grillcloth on it (yes I know it's a little crooked but he IS 81), built a new power transformer, replaced two pots, and cleaned it up as much as possible. I recently bought a 1966 CTS Ampeg custom speaker for it, too, which was a great improvement over the Eminence. It's still not the prettiest B-15N you'll ever see, but it's a Jess Oliver resto and has a nifty little certificate inside! It's amazing how modern it sounds. The cab has a strong upper mid and a warm but tight bottom end, and the CTS has a very strong high end for a 15".

The other one is a 1977 B-15N I bought a month and a half ago from Bass Central. It's in a lot better shape, although it had a broken latch and a pretty dirty grill that I've cleaned up quite a bit. It didn't have a dolly and I bought an early 70's dolly for it from Ebay just to have one, but it doesn't match the tolex of the cab, so if anyone has a dolly with the proper tolex, I'm interested. The speaker is a 1970 CTS, which was apparently switched to Eminence by the time this cab came out. I'm not complaining, though. It's a lot darker than the 66 CTS, and highs past about 2K are non-existent, but the low mids and lows are so great in this cab that you don't care. This has been my main gigging amp since I got it. It's so completely different than anything else I've used in the past, and I'm really digging its ability to pummel its way through a mix as opposed to cutting through like the other cabs I have. I'm also amazed at how I'm able to nail the recorded tones of a lot of the songs we do with this amp. It's by far the amp that people who work with me like the best because it sounds like BASS, so now I try to emulate it in every amp I use.

I'm looking forward to hearing the stories behind your Fliptops as well. There are a lot of us who have them on here, so let's all get together and gloat!

EDIT: Geez, that's a bad pic...I'll try to replace it with a better one tomorrow when I can take them out in the light.

SECOND EDIT: Anyone with an Ampeg Bassamp from 1960 or before is also eligible for the club.

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I've got the B-15 reissue. I wanted a 'smaller' amp that I could still gig with some volume, and did get to A/B the reissue in the store with a '66 B-15N. The 100w proved to pump some volume.
About a year later after alot of searching, I found a guy across country selling an extension cab, and made it happen although he was leary of shipping and it getting damaged. The sound is rather large, and it has been a great recording amp.

Forgot to mention. I changed out the sucky stiff sounding groove tubes, and installed JJ/Tesla E34L tubes. The tone really blossomed and opened up.

Dig...Justin Meldal-Johnsen used a B-15R with a mic and no DI on Beck's Sea Change album. I've never even seen one, and now they've been disco'ed so who knows if I ever will. Looks like a cross between the B-15N and a V4B. Gets mixed reviews, but I'll bet it kicks much ass.

I bought it from a guy in Florida and Fedexed it o Australia about 6 months ago. The power transformer needed replacing with a 230V version from Fliptops.net. (The original PT was some butt ugly generic replacement transformer). I also did a bit of restoration work on the cab to clean up a fair bit of rattling and buzzing...{}
I use it whenever I can- only when I know the band I'm playing with isn't going to drown it out.

You should post a link to your resto thread here and all the trouble you had with rattles. Apparently tolex in the port holes is the usual thing, because Jess did it, too. But it comes loose and causes rattling, so you did the right thing. Controlling rattle in a B-15 is tough, so we should devote a good portion of this thread to that.

I have 3 B15N heads that are awaiting cabinets, as well as a B12N and B12XT with repro cabinets, so I won't post pictures of those. However, I have a '67 Oliver P502 Powerflex that I just picked up in March.

I got it pretty cheap because it was a mess and the amp didn't work. It turns out that the reason it wasn't working was that it was missing the rectifier tube. Once I put one in it started working, but it still sounded bad. It seems that someone installed a bogus 20w resistor in the power supply (5 ohm instead of the correct 5k ohm). Once that was fixed it started sounding pretty good. It's still not 100% but it's getting there.

The cabinet took alot of work but it ended up looking nice. I decided to make a new baffle for it since the wood in the old one was all split where the attachment screws ran into it. I also had to make a new dolly, since that was missing, too. I was going to install an Altec 421A speaker in it but the magnet was too big. The elevator platform could not retract all the way because it hit the magnet. Instead, I installed a JBL K130 and it sounds pretty nice.

I just posted the photos I took while working on the cabinet. You don't see many photos of the Oliver amps, and I've never come across any that showed the interior. If you're interested you can see them here: http://www.vintage-blue.us/p502/p502.htm.

Here's my 1967 B-15N. I picked it up on ebay a few months back from a guy a few miles outside of boston. I actually ended up driving to his house about an hour after winning the auction to pick it up. He said he had a few of these amps and that the head on this was a 67 but he thought the cab was from an older (64/65) model, which is also where he got the chicken head knobs. The speaker is a square-mag CTS and I checked the code and it came up as being made in 67 so I'm not so sure about his story with cab. It came with all the original pre-amp tubes as which I put back in since they sounded a lot better than the ones he had replaced them with. I love this amp and have done all my recent recording with it, hopefully, some of those songs will be mixed soon and I can go back and listen to them haha.

Here's my '73 B-15N with a Dark Star P-bass. Not shown is a '75 that's getting new 4-pin jacks, and a cool '68 that I sold. In the background is an autographed photo that Jess Oliver sent me after we exchanged a few emails. To the right is a 1953 RCA Victor TV cabinet with a mono amp for playing records, and a 12" speaker...which became my "practice amp" in the 60s.

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Here's my '73 B-15N with a Dark Star P-bass. Not shown is a '75 that's getting new 4-pin jacks, and a cool '68 that I sold. In the background is an autographed photo that Jess Oliver sent me after we exchanged a few emails. To the right is a 1953 RCA Victor TV cabinet with a mono amp for playing records, and a 12" speaker...which became my "practice amp" in the 60s.

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Damn I bet you have some amazing tone with the darkstar and that amp....

How much do the b15s run for anyway? I'd love to get one for my recording setup...

Good going, VB! I thought it would take much longer for someone to show detailed pics of their Oliver! I know you're big on the double baffle cab, but any experience with the Thiele cabs where you could give us your thoughts on how they compare? Jess thinks they completely lifted his cab design, and quite honestly, I think there's some merit to that when you consider the timelines. But there are some differences...Jess' cab looks more like what they used for the B-15S in the 70's.

BTW, may I say that your repro double baffle cabs are absolutely beautiful? I have a Fliptops repro cab that I'm very happy with the workmanship, but had I known you existed at the time, I might have gone with one of yours. I love how you go the extra mile and stain the exposed wood like the originals. Nothing against Bruce Michelli at all because he's been very good to me and does great work, but I call 'em as I see 'em.

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Visirale, B-15's vary wildly in price depending on condition. I've seen some outrageously good deals on them (like the $150 I paid for my 64), and I've seen some just plain outrageous prices (Bass Central wanted $1500 for the 77, I talked them down to $1000 after showing them a couple Ebay auctions where they went for significantly less than $1500, and I still think I paid a little too much, but it was convenient and I wanted it!). Check Ebay because they always have 3 or 4 B-15's for auction.

Here's my 1967 B-15N. I picked it up on ebay a few months back from a guy a few miles outside of boston. I actually ended up driving to his house about an hour after winning the auction to pick it up. He said he had a few of these amps and that the head on this was a 67 but he thought the cab was from an older (64/65) model, which is also where he got the chicken head knobs. The speaker is a square-mag CTS and I checked the code and it came up as being made in 67 so I'm not so sure about his story with cab.

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Ya, the cab is almost definitely a 67. It's the single baffle design. If it were a 64, it would be the double baffle with a Jensen P15N. Personally, I like the CTS better. And recently a guy posted a thread about B-15's and got to try all the cabs, and he went home with a 66 similar to yours. So it's all good! Except for the chicken head knobs. When I sent mine to Jess, he informed me that there were stove-top knobs on B-15's, not chicken heads, and he actually seemed to express disdain for the chicken heads. Probably because they were a Fender thing

Good going, VB! I thought it would take much longer for someone to show detailed pics of their Oliver! I know you're big on the double baffle cab, but any experience with the Thiele cabs where you could give us your thoughts on how they compare? Jess thinks they completely lifted his cab design, and quite honestly, I think there's some merit to that when you consider the timelines. But there are some differences...Jess' cab looks more like what they used for the B-15S in the 70's.

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Sorry, I've never had the chance to check out a Thiele cabinet so I can't say how they compare.

I don't know if Ampeg tried styling any of their designs after Jess' but I do know that Jess incorporated some of his Ampeg designs into his Oliver amps. His Powerflexes used the same Stimpson closed eyelets for foot cups (he used the matching open eyelet for the trim rings). He also kept the same spacing, so a B15 dolly should fit a Powerflex. Jess varied handle styles periodically, but for a time he used the same Kason chrome side handles that Ampeg used on some of their amps. Although my P502 originally came with leather strap handles, I found that the sides had been pre-drilled for the Kason handles.

Nope, not original. The previous owner replaced the black vinyl at some point. He also installed a 3 prong power cable.

I'm just learning about these amps. The serial on mine checks out to 1966, but the speaker is a Jensen C-15. Ampeg had switched over to CTS speakers by this point, yes? Also, is there any easy way to check if I have a single vs double baffle cab? If it is a 1966 it should be a single baffle, right?

Right. But it should have come with a CTS, not the Jensen. Lift up the fliptop, and if you have 8 oval shaped holes surrounding the speaker hole, it's a double baffle. I can't tell which it is in your pics, quite honestly. You can usually tell because the front frame is larger and the grill is more set into the frame.